Initially a gas of diatomic molecules is contained in a cylinder of volume V1 at a pressure P1 and temperature 250 K. Assuming that 25% of the molecules get dissociated causing a change in number of moles. The pressure of the resulting gas at temperature 2000 K, when contained in a volume 2V1 is given by P2 . The ratio ${{{P_2}} \over {{P_1}}}$ is ________.
Answer (integer)
5
Solution
We know, PV = nRT
<br>$\therefore$ P<sub>1</sub>V<sub>1</sub> = nR (250)
<br><br>and P<sub>2</sub>(2V<sub>1</sub>) = ${{5n} \over 4}R \times \left( {2000} \right)$
<br><br>By Dividing
<br><br>${{{P_1}} \over {2{P_2}}}$ = ${{4 \times 250} \over {5 \times 2000}}$
<br><br>$\Rightarrow$ ${{{P_1}} \over {{P_2}}} = {1 \over 5}$
<br><br>$\Rightarrow$ ${{{P_2}} \over {{P_1}}} = 5$
About this question
Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law
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